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    <div class="example" id="variadic-functions">
      <h2><a href="./">Go by Example 中文版</a>: 变参函数</h2>
      
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            <p><a href="https://zh.wikipedia.org/wiki/%E5%8F%AF%E8%AE%8A%E5%8F%83%E6%95%B8%E5%87%BD%E6%95%B8"><em>可变参数函数</em></a>。
在调用时可以传递任意数量的参数。
例如，<code>fmt.Println</code> 就是一个常见的变参函数。</p>

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            <a href="http://play.golang.org/p/Yk00SL5urA-"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
          <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
</pre></div>

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          <div class="highlight"><pre><span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
</pre></div>

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            <p>这个函数接受任意数量的 <code>int</code> 作为参数。</p>

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          <div class="highlight"><pre><span class="kd">func</span> <span class="nx">sum</span><span class="p">(</span><span class="nx">nums</span> <span class="o">...</span><span class="kt">int</span><span class="p">)</span> <span class="p">{</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Print</span><span class="p">(</span><span class="nx">nums</span><span class="p">,</span> <span class="s">&quot; &quot;</span><span class="p">)</span>
    <span class="nx">total</span> <span class="o">:=</span> <span class="mi">0</span>
    <span class="k">for</span> <span class="nx">_</span><span class="p">,</span> <span class="nx">num</span> <span class="o">:=</span> <span class="k">range</span> <span class="nx">nums</span> <span class="p">{</span>
        <span class="nx">total</span> <span class="o">+=</span> <span class="nx">num</span>
    <span class="p">}</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">total</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>

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          <div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
</pre></div>

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            <p>变参函数使用常规的调用方式，传入独立的参数。</p>

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          <div class="highlight"><pre>    <span class="nx">sum</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
    <span class="nx">sum</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
</pre></div>

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            <p>如果你有一个含有多个值的 slice，想把它们作为参数使用，
你需要这样调用 <code>func(slice...)</code>。</p>

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          <div class="highlight"><pre>    <span class="nx">nums</span> <span class="o">:=</span> <span class="p">[]</span><span class="kt">int</span><span class="p">{</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">4</span><span class="p">}</span>
    <span class="nx">sum</span><span class="p">(</span><span class="nx">nums</span><span class="o">...</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>

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          <div class="highlight"><pre><span class="gp">$</span> go run variadic-functions.go 
<span class="go">[1 2] 3</span>
<span class="go">[1 2 3] 6</span>
<span class="go">[1 2 3 4] 10</span>
</pre></div>

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            <p>接下来我们要看的是 Go 函数的另一个关键特性：闭包。</p>

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        下一个例子: <a href="closures">闭包</a>
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